The present invention relates an improved unbalance audit machine intended for use in the manufacture of tires. The molding and manufacture of tires having various profiles and sizes is plagued by the inability to accurately and rapidly grade the tires after the completion of manufacture. An important aspect of tire grading involves the determination of the location of any heavy spots or points of unbalance in the newly manufactured tire. If the unbalance is determined to be within preset tolerance standards, the tire is given an appropriate grade and passed through to shipping. If, however, the measured tire unbalance is outside of the preset tolerances, the tire must be scrapped.
Achieving closely accurate unbalance auditing of manufactured tires coming through an assembly line is complicated by the variety of profiles and sizes of tires and, also, the flexibility of the newly manufactured and unmounted tire. Further, differing styles of tires, such as steel belted radial and bias ply tires create varying strength characteristics affecting the support of the tire during unbalance auditing.
Repeatable and accurate unbalance audit operations require precise support and positioning of each incoming tire of the unbalance measuring machine. The centerline of the tire must accurately match the centerline of the unbalance measuring machine and the tire must be maintained in a level position with respect to the centerline of the unbalance measuring machine. These centering and leveling requirements often make the unbalance audit operation time consuming and complex, thus interfering with the quality and efficiency of manufacture.